Tow processing machines



G. M. JEFFREY ETAL 3,106,326

TOW PROCESSING MACHINES Oct. 8, 1963 2 Sheets-Sheet 1 Filed Dec. 28, 1960 INVE NTORS GEORGE. MnLcoLn JEFFREY NH-URN ocus.

81 R QINEIS Oct. 8, 1963 G. M. JEFFREY ETAL 3,106,326

TOW PROCESSING MACHINES Filed Dec. 28, 1960 2 Sheets-Sheet 2 IrNsNToRS one: Mmmm ISEFFREY wmuan Pooua BY ATTORNEYS m Mil United States Patent 7 O 3,106,326 TOW PROCESSING MACHINES George Malcolm Jeffrey and 'William Poole, Coventry, England, assignors to Courtaulds Limited, London, England, a British company Filed Dec. 28, 1960, Ser. No. 78,886 Claims priority, application Great Britain Dec. 29, 1959 7 Claims. (Cl. 226-177) This invention concerns tow processing machines of the type in which a fibre bundle of heavy denier (e.g.'

of the order of hundreds of thousands and more) is passed between nip rollers. By fibres we mean both continuous filaments and staple fibres.

When nip rollers are used for manipulating tows of heavy denier, it is often necessary to compromise roller efiiciency with roller diameter, in that the operating requirements of the nip rollers may dictate the use of rollers which are inconveniently and inefficiently large and cumbersome. For example, when it is desired to impart stretch to the component filaments of a tow of heavy denier, a more efiicient nip (i.e. greater nip pressure) is required than when the rollers are being used simply to advance the tow. Thus'in a tow-to-top machine in which the tow is stretched to the filament breaking point between two pairs of nip rollers, it is necessary to employ a relatively high nip pressure and this suggests the use of heavy rollers of large diameter to transmit the pressures involved. Since, however, the maximum staple length which results is determined by the distance between the two nips, this in turn is controlled at its lower limit by the closeness of approach of the two pairs of.

nip rollers, which in turn cannot be less than the mean diameter of the rollers of the two pairs (assuming that the rollers in each pair are of equal diameter).

In other words, when tow denier may suggest the use of rollers :of relatively large diameter, other considerations (such as required low staple length in a tow-to-top machine) may dictate the use of smaller rollers.

A further complication results from the fact that it is usually desired to leave one end of the nip open in order to allow convenient threadingmp of the machine at high tow speeds.

Another disadvantages arises when both rollers of a pair are to be driven positively, instead of one of them relying on a frictional drive from the other roller through the tow. The most convenient arrangement is to drive one roller through gear wheels from the other roller shaft. For example, a gear wheel on one roller shaft may be driven from a gear wheel on the shaft of the other roller. However, direct intermeshing of the two gears is an inefficient arrangement because the rollers are normally covered with a compressible material such as rubber and the spacing of the nip rollers may therefore vary in running. rectly, tolerance in the mesh must be allowed to cornpensate for nip variations.

An obvious alternative is to link the gears via two intermediate gear wheels, but the problem of fitting two extragear wheels into the space, between the roller shaft gearwheels becomes much more difficult whensmall diameter rollers are employed.

There is a need for an alternative arrangement for coupling the drives to the rollers of a pair of nip rollers.

Finally it is dilficult to provide a positive drive to both rollers while at the same time allowing for adjustment of the nip.

According to the present invention, inrespect of these various problems which arise when it is desired to provide a positive drive to both rollers of a pair of nip rollers, especially when the nip is to be adjustable, or when If the two gears are to mesh dismaller rollers or greater nip pressures are required, an improved mechanism possesses one or more of the following features: r r

(1) At least one of the rollers is supported at both ends in a cantilevered mounting, i.e. one which is supported from a point adjacent to one end of said roller;

2) A gear mounted on the shaft of one of the rollers or fixed to an internal annular gear on the same shaft,

and a third gear wheel mounted on the shaft of the Second roller engages the internal anular gear.

In a particularly preferred form, the second roller is mounted eccentrically in a housing which is rotatable about an axis co-linear with the axis of the annular gear.

It will be seen that rotation of the housing moves the roller axis through an arcuate path about the axis of the housing as centre (which movement may be arranged to move the second roller towards or away from the first roller) and that a gear mounted upon the shaft of said second roller and engaging the annular gear, will remain in engagement as the nip is varied.

Other possible variations of the detail of the present invention will be apparent from the following description 'of a tow-totop machine according to the present invention shown in the accompanying drawing, in which;

FIGURE 1 is a simplified general elevation of the machine,

FIGURE 2 is a vertical section of the front stapling rollers and associated parts of the machine, and

FIGURE 3 is a simplified elevation corresponding to FIGURE 2.

Referring firstly. to FIGURE 1, a tow 1 of continuous filaments, for example a 480,000 denier tow of polyacrylonitrile filaments of 1% denier per filament, passes over tow guides 2, for aligning and spreading the tow, and

then between a pair of stretch rollers 3, 3a. The tow then passes over two sets of snubbing rollers 4 and 5, and on to a second pair of nip rollers, the back stapling rollers 9, 9a. The rollers 9, 9a rotate at a greater peripheral speed than the rollers 3, 3a and a stretch is therefore imparted to the filaments in the tow in a hot-stretch zone between the two sets of sunbbing rollers. The hotstretch Zone comprises a fiat channel 6, formed between air chambers 7 and 8 in a hot air cycling system such .as that described in the specification of our co-pending application No. 856,849. The effect of the hot-stretch treatment of the tow is to impart to the filaments a high degree of potential shrinkage, the srinkage being brought about at a later stage by immersion of the filaments in a hot aqueous liquid or vapour. However, even when it .is not desired to produce high-shrinkage top, it is debetween the hips formed on the one hand by the back stapling rollers 9, 9a and on the other hand by a front pair of stapling rollers '10, 10a. Between these two pairs of nip rollers, and close to the 'back rollers 9, 9a, are located a pair of electrical radiant heaters 12. The degree of draft between the two pairs of nip rollers is sufficient to break the continuous filaments. While inevitably some of the filaments will break at points in the ratch other than between the heaters 12, a majority of the filaments will break within the heating zone and the average length of the staple in the top formed will correspond approximately to the distance between the heating zone and the nip of the front stapling rollers. To ensure uniformity of the top formed (by staggering the points of breakage from filament to filament) the leading edge of the tow is tapered before presentation to the front stapling rollers during threading up of the machine.

Stray filaments adhering to the stapling rollers are [rernoved by brushes 11.

The front stapling rollers are carried upon a carriage 13, designed to run along a track 14, so that the distance of the front stapling rollers from the heating zone, and thus the average staple length produced, may be varied. It will be seen by reference to FIGURE 2 (in which like numbers refer to like parts) that the carriage 13 is moved along the track 14 by turning a hand wheel 15 and so rotating a pinion wheel =16 in engagement with a rack 17 mounted upon the carriage 13.

FIGURE 2 of the drawing shows the drive to the front stapling rollers in greater detail. The rollers and 10a are mounted respectively upon shafts 19, 19a supported within bearings beneath the carriage 13. The shaft 19 is carried directly by a frame 33 slung below the carriage '13, while the shaft 19a is supported for rotation within a cylindrical housing 20 which in turn is carried by the frame 33. As will be seen from FIGURE 3, the shaft 19a is mounted eccentrically with respect to the axis of the housing 20. The outer end of the shaft 19a is supported in bearings within a cantilevered extension 21 of the housing 20 in such a way as not to obstruct direct access to the nip of the rollers.

, The drive to rotate the shaft 19 is applied to the roller assembly by a double chain drive to a double sprocket wheel 22, mounted upon the shaft 19. A gear wheel 23, keyed to the shaft 19 at 23a, transmits the drive to the upper roller shaft 19a via an external gear 24, an internal annular gear 241: integral with the gear 24, and a spur wheel 25, mounted upon the roller shaft 19m and meshing with the internal gear 24a. The member comprising the gears 24 and 24a is supported upon a lay shaft 26.

The gear wheel 23 forms the movable member of a clutch linking the upper and lower roller shafts and by operation of a clutch lever 27 (pivoted at 27a) may be moved axially out of engagement with the gear 24. It is thus possible to drive the upper roller 10a positively or, by disengaging the clutch, to leave the upper roller to rotate simply by frictional engagement through the tow with the surface of the lower roller 10.

All of the nip rollers illustrated in FIGURE 1, viz roller-s 3, 3a, 9, 9a, 10 and 10a, are rubber covered and both roller 10m and roller 90 are driven in a similar manner through a clutch like that described :above and illustrated in FIGURE 2. The rollers 3a, 9a and 10a may be swung into and out of closer contact with the lower rollers 3, 9 and 10 respectively so as to vary the respective nips. In each case, the adjustment is obtained by rotating a cylindrical housing within which the upper roller shaft is mounted eccentrically. This feature of construction in the case of the front stapling rollers will now be described by reference to FIGURES 2 and 3 of the drawring.

The roller housing 20 is surrounded by an annular external worm wheel 32 meshing with a worm 31. By rotation of a hand wheel 28, the worm 31 is rotated via intermediate gear wheels .29 and 30.

The annular internal gear 24a is coaxially aligned with the cylindrical housing 20. As a result, when rotation of the housing 20 moves the axis of the roller 19a in an are about the axis of the housing 20 as centre, the gear wheel 25 remains in mesh with the internal gear 2411. This means that, whatever the position of the upper roller 10a relative to the lower roller 10, when the clutch is engaged the upper roller is driven positively.

From the tow-to-top section of the machine, the top passes on, if desired through a crimper of conventional design, to a suitable collecting device or to processing equipment suitable for converting the top to yarn.

What we claim is:

l. A pair of rollers for conveying a fibre bundle, a gear wheel fixed upon a first shaft carrying a first roller, an external gear on a second gear wheel engaging the first gear Wheel and mounted for rotation on a second shaft parallel to the first shaft, an internal annular gear on said second shaft and fixed to rotate with said external gear, and a third gear wheel fixed upon a third shaft carrying the second roller, the third gear wheel engaging the internal annular gear, the second roller being mounted for movement towards and away from the first roller along an arcuate path, the internal annular gear being concentric with the circle of which the arcuate path is an are.

2. A pair of rollers for conveying a fibre bundle, a rotatable housing in which one of the rollers is mounted eccentric to the axis of rotation of the housing, a gear wheel on the shaft of that roller, and an internal annular gear, engaging said gear wheel and having its centre co-linear with the axis of rotation of the housing.

3. A pair of rollers as claimed in claim 2, in which said internal annular gear is rotatable by a gear on the shaft of the other roller.

4. A pair of rollers for conveying a fibre bundle and both mounted upon shafts, one of said rollers being mounted for movement perpendicular to its longitudinal axis along an :arcuate path towards and away from the other roller, an internal annular gear mounted to rotate about an axis perpendicular to the plane of said arcuate path and passing through the centre of the circle of which the path is an arc, and a gear wheel fixed to the shaft of said movable roller and engaging said annular gear, whereby when the movable roller moves along said arcuate path said gear wheel remains in engagement with said annular gear.

5. A pair of rollers as claimed in claim 4, having means to rotate said internal annular gear.

6. A pair of rollers as claimed in claim 4, in which said internal annular gear is rotatable by rotation of the other roller.

7. A pair of rollers as claimed in claim 4, in which said internal annular gear is rotatable by means of a gear associated with the other roller.

References Cited in the file of this patent UNITED STATES PATENTS 1,946,170 Mileaelson Feb. 6, 1934 2,016,130 Wren Oct. 1, 1935 2,748,426 Wyatt June 5, 1956 

2. A PAIR OF ROLLERS FOR CONVEYING A FIBRE BUNDLE, A ROTATABLE HOUSING IN WHICH ONE OF THE ROLLERS IS MOUNTED ECCENTRIC TO THE AXIS OF ROTATION OF THE HOUSING, A GEAR WHEEL ON THE SHAFT OF THAT ROLLER, AND AN INTERNAL ANNULAR GEAR, ENGAGING SAID GEAR WHEEL AND HAVING ITS CENTRE CO-LINEAR WITH THE AXIS OF ROTATION OF THE HOUSING. 